


girl flex

by leftishark



Category: Voltron: Legendary Defender
Genre: Alternate Universe - Modern Setting, F/F, Gay Disaster Shiro (Voltron), Genderswap, Podfic Available, Sheithbians, gratuitous commentary on weight room etiquette, lesbian edition
Language: English
Status: Completed
Published: 2019-01-17
Updated: 2019-01-17
Packaged: 2019-10-11 09:57:32
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,293
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17444699
Author URL: https://archiveofourown.org/users/leftishark/pseuds/leftishark
Summary: Keith tries to rescue Shiro from awful gym bros. Shiro tries to woo Keith with her muscles.Keith saves her from her mental gymnastics when the silence stretches too long. “Look, how about we share,” she offers. “We can spot each other.”Shiro has a vision of herself watching Keith’s muscles work as she stands behind her for safety. It’s a brilliant solution, speaking to Shiro’s core values of teamwork and lesbianism. “Yeah, okay,” she agrees. “Okay, cool.”





	girl flex

**Author's Note:**

> throws 3k of disaster muscle girls into the void and runs away
> 
> (tiptoes back: [this is what a power rack looks like](http://www.fitstrength.com/strength-equipment/powerrackslifting.htm) for anyone who needs it)

Shiro’s morning routine is sacred. Wake up at 6AM, get to the gym at 6:30. Cardio, free weights, power rack, stretch. Shower at 7:30. Then at 7:45 she refills her water bottle by the entrance so she can time her exit to glance at the cute girl who always wears red as she swipes into the gym.

(Shiro manages eye contact occasionally. Most of the time, she chickens out when she gets too close and fumbles for her keys instead.)

There are good reasons for this particular timing, besides her hopeless almost-flirting. One is that the weight room gets crowded around 7:30, and she avoids dealing with more men than she has to. The other is that she finishes up early enough to clear out her inbox and take care of any last-minute grading over a protein shake before classes and meetings start for the day.

But Shiro’s phone has been glitching lately, and it died sometime during the night. She’s overslept by nearly an hour, knocked out from the buildup of several late nights grading midterms. Skipping the gym is out of the question—leg day is her favorite—so she scrambles to grab her things and braces herself for the crowds.

Traffic, she realizes, is another reason she maintains her early regimen. She arrives grumpy and frazzled and even later than expected to a weight room predictably full of frat boys grunting through heavier sets than they can really handle. 

After warming up on the treadmill and thoroughly stalking the crowded power racks, she finds herself doing aggressive calf raises as she waits for two big dudes to finish gossipping in the cage in front of her. 

She’s tried the polite approach already, asked them blandly how many sets they had left. 

“Just a few,” they said. “We’ll be out in, like, five minutes.” 

It’s been fifteen.

At the ten minute mark she even followed up with a passive aggressive walk-by. She’s been told her side eye can crumble mountains, but these men are willfully oblivious. 

Shiro has gone through her whole ab routine by now—planks, crunches, side planks, side crunches. She’s running out of bodyweight exercises she can do from her post behind the cage that fit the workout she planned for today. Calves are a second heart, her mom says when they talk about health stuff—so, often—and Shiro likes how she has sculpted her own through diligent training. But nobody needs to do this many calf raises. 

She’s considered that another rack could clear out before this one, and there’s one just further down that may have been abandoned; there’s a water bottle on the floor and weights on the bar, but those are left behind as often as they are deliberate placeholders. At this point, though, it’s a matter of principle. She’ll settle for no other. 

She curses men and their terrible gym etiquette. 

She’s glaring at the two in front of her through the mirror, wholly ignored and considering another confrontation, when sudden movement breaks into her peripheral vision, swift and focused. 

It’s the girl in red.

Shiro forgets her frustration for a blissful moment, distracted by the girl’s disheveled hair and sculpted shoulders. They’re broad where they emerge from her loose tank top and tensed as she stomps toward the cage where Bro 1 and Bro 2 are going on and on about the exercises that they’re _not doing_. Shiro drops sharply down to her heels when she realizes the girl is about to do something, to say something to them—

“Will you fucking clear out of the _fucking_ cage,” she snarls. 

It’s a good thing Shiro is on two solid feet because her heart rate jumps and her knees go wobbly. The girl’s voice is rich, forceful, and she’s a full head shorter than the shorter guy yet she radiates the power of a—a raging fire, a great typhoon, her ferocity towering over them. 

The dudes turn sharply, taken aback, and when they recover they wield condescension in defense. “Keith,” the tall one sneers. “Always picking fights you can’t win.”

“Fuck off, Zarkon,” the girl—Keith—spits. “Get out so someone can actually use the weights. You know, for _lifting_?”

“Who's gonna make us do anything?” the shorter one goads. “It’s a free fucking country.”

Keith takes a threatening step towards him, and Shiro snaps out of her daze. As validating and brain-meltingly hot at it is to watch her go at them, she doesn’t want any real trouble. 

“Hey, man,” she breaks in, moving as calmly as possible to stand by Keith’s side facing the others. “It’s just a squat rack.” 

She can feel Keith’s eyes on her as she stares down the two dudes, and she summons all her training in conflict de-escalation as their eyes narrow. But maybe the guys recall their earlier exchange with her and have some hidden ounce of honor, or maybe she just looks intimidating enough that they don’t want to keep going. Whatever it is, it’s enough to make Zarkon back down with a scoff and an eye roll.

“Whatever,” he mutters. “C’mon, Sendak, we’re done here anyways.” The two of them grab their phones and water and slouch off, leaving their weights rudely behind. 

Then it's just Shiro and Keith and the squat rack. 

Several long seconds go by between them in silent acknowledgement of what just passed. Telling off rude boys wasn’t the way Shiro had ever imagined talking to her long-standing gym crush, had preferred fantasies of catching her eye with biceps bulging around dumbbells, or back and shoulders flexing the top of a pull-up, when she let her mind wander that way. She wasn’t at all prepared for Keith, who always almost-smiled at her, her face and build all graceful angles, swooping in to fight off a couple of hulking bros. 

Still staring at the vacated cage, Shiro clears her throat at the same time that Keith draws a breath to speak. 

She breaks off. So does Keith. 

Fearing an impasse, she looks over just as Keith turns to her. A tactical error: she’s never seen Keith this close before, and her eyes are dark and wide and so, so beautiful. Shiro loses herself for a moment before gathering the last functional pieces of her mind: she has a mission, now, to ensure that this incredible girl gets her rightful weight rack. 

She clears her throat again and gestures at the cage. "All yours." 

"What?" Keith says, startling. Her whole face is so expressive, dark brows turning up and pretty lips turning down. “No, you take it. It’s yours.” 

"What are you talking about? You confronted them," Shiro urges. “That was really something.” 

"Yeah, well,” Keith says, looking a little lost. She reaches up to tighten her ponytail. “You talked to them first." 

Shiro doesn’t know what to say to that, all her struggling brain power diverted to the flex of Keith’s arms around her head and the realization that Keith had noticed that encounter—does that mean she’s been eyeing the cage as long as Shiro has? Does it mean she’s been watching _Shiro?_

Keith saves her from her mental gymnastics when the silence stretches too long. “Look, how about we share,” she offers. “We can spot each other.”

Shiro has a vision of herself watching Keith’s muscles work as she stands behind her for safety. It’s a brilliant solution, speaking to Shiro’s core values of teamwork and lesbianism. “Yeah, okay,” she agrees. “Okay, cool.” 

It occurs to her once they remove the leftover weights that they’re about six inches apart in height, so to show she’s not totally useless she steps into the cage and lowers the hooks that the bar rests at a height suitable for Keith. She can always bend a little lower. “Cool. Um. I’m on back squats today.” 

“Go ahead,” Keith insists. 

Shiro is hopeless at talking to pretty girls, but this, she can do. 

By unspoken agreement they start with just the bar, 45 pounds to remind their muscles of the proper motion. Keith’s form is excellent, Shiro observes when they switch off, her chest upright and her ass pressing back as she dips low. Shiro has to snap her eyes back to the bar at the end of her set. 

Keith raises an eyebrow in question as they move to opposite ends of the bar to add the first weight.

"A plate," Shiro says, so they each add one of the standard 45 pound circular weights to the bar. It's 135 pounds total now, and maybe she should have started with a lower weight in case Keith doesn’t lift as much—the 25 or 35 pound weights, so they could easily add and remove more without dismantling the whole set-up. But she’s always thought it looks sexier to use one of the big plates than two or three of the smaller ones. This is her best asset, and she’s going to work the hell out of it. 

As it turns out, Shiro didn’t need to worry about the weights. “Leave it,” Keith says when they switch, a little cheeky as she steps up to the bar. 

What she needed to worry about was her own reaction to the fact that Keith can, in fact, lift what must be her own bodyweight. Not that she’s surprised, exactly, seeing as Shiro can theoretically squat one and half times her own, but Keith just looks so _small_ , wide-shouldered but narrow everywhere else, muscles defined but lean rather than built. Her ass and thighs are visibly straining under the heavy weight, and Shiro flushes with the sudden urge to feel them under her hands—

Keith lets out a sharp grunt of effort, and Shiro remembers that she’s supposed to be spotting her. She shuffles closer, taking a stance just out of range of Keith’s ass so she can bring her hands up to hover under the bar. Like this, she’s safe from staring at Keith’s rear, but she’s close enough to feel her warmth, and when she glances up she catches sight of them in the mirror, Keith’s face intensely focused and her own dazed one poking out above it because she’s _that much taller_. 

She can’t decide if the mirror is her friend or her enemy.

Keith steps forward to set the bar on the hooks, out of her space, and Shiro collects herself as they move to switch places again. This might be her only chance to talk with this subtly buff, stunningly fierce, really really hot girl. She clears her throat yet again.

“Sorry, by the way,” she says. “For interfering earlier. I didn’t mean to step on your toes or anything.”

“S’all right,” Keith shrugs. She looks embarrassed, one arm clasped to the other as she shifts on her feet. “Thanks, really. Sometimes I get. Y’know.” She shrugs again, glancing away.

“They seem like real assholes,” Shiro sympathizes.

“Yeah, they’re the worst,” Keith scowls. Then she looks over at Shiro, a bold tilt to her chin. “I’m glad you don’t think I am.”

“No way,” Shiro says vehemently. If that’s why she’s being cagey, Shiro wants to dispel any doubt. “You saved me. Seriously, I have no idea how long those guys were gonna stand there.”

“We saved each other,” Keith allows with a small smile.

Shiro's face heats. She can’t tell if Keith is flirting with her, can’t even tell if she’s managing to flirt with Keith. She can at least make sure she knows her name. 

“It’s Keith, right?” She smiles at Keith’s nod. “My name’s Shiro.”

Keith’s brow scrunches up, and then her eyes go wide. “Wait, Shiro as in Shirogane? From the record board?” 

Shiro does a sort of nod-shrug-grimace in affirmation; she catches it in the mirror and decides the mirror is not, in fact, her friend. As proud as she is of her physical strength, she’s feels weird about it being displayed, not on her own terms, as if the university gym is claiming her accomplishments. There’s no denying it, though—lifting has been one of the few constants in her life since she was a teenager, and training extra hard is keeping her sane through grad school. The results are clear on her body and the gym wall.

“Holy shit,” Keith says, running a hand through the strands of hair around her face that have fallen out of their clip as she paces back and forth. She waves at the weights they’ve set up. “What’s with this? You’re holding out on me!” 

“It’s good to warm up,” Shiro deflects, unprepared for such an impassioned response.

“Yeah, okay, you’re warmed up now, right?” Keith persists. “Show me what you’ve got.”

So Shiro holds up another weight, and Keith adds a matching one to her side of the bar. 185 pounds is toward the upper end of her range, the bar digging heavy into her trapezius muscles between neck and shoulder. She knows she looks good like this, can see the reflection of her own quads bulging as she sinks down and surges back up. Thank god she wore booty shorts today. Her height and bulk are blocking Keith from the mirror, but she hopes she’s appreciating the view from behind. 

“Nice form,” Keith grins when she racks the bar. “You know, those records up there are what got me to start lifting seriously in the first place.” 

Shiro laughs sheepishly and scratches at the buzzed stubble at the back of her head. “Yeah?” 

Keith nods, enthusiastic. “I’ve done a lot of martial arts and other stuff, but not this. When I saw those numbers, I thought if those women—girls—whatever—can do it, so can I. Figured it might make people take me more seriously, since I’ve always been, you know, kinda small. ” She pauses, expression turning down. “Not that it made a difference.” 

“Hey,” Shiro says gently. “I bet you could’ve kicked both their asses.” She genuinely believes it. Keith is small, yes, but Shiro infers that she is skillful and clever and knows that she is strong. 

“Sure,” Keith scoffs, quietly sarcastic, kicking at the floor, “that’s why you stepped in.” 

“I was afraid that you would,” Shiro says, grasping at boldness. “What would I do if my hero got kicked out for slaying a man?” 

Shiro is definitely flirting now, badly, but she thinks it’s not unwelcome when Keith’s eyes go wide (and dark and beautiful) again before she settles into a crooked smile and moves to adjust the weights. 

Shiro thinks of the numbers on the wall, and decides that if they inspire other women, inspire Keith, then Shiro’s okay with them, too. 

Two more sets each, weights on and off and bits of small talk here and there, and then they agree to wrap up after one more. Shiro is loathe to end the most enjoyable workout of her life, but she can feel her muscles getting shakier, sweat soaking her hair and her shirt. 

Keith is sweaty, too, and as they’re pausing to catch their breath she pats the collar of her tank top over her neck, then pulls the bottom edge up to wipe off her forehead. It exposes her stomach for the first time, and—wow. Shiro’s thirst returns in full force with how tiny her waist is, abs defined in light shadow. 

Struck by sudden inspiration, Shiro reaches up to tug her own over shirt her head; she's hot, and the basic T-shirt cut isn’t doing anything for her frankly impressive upper body. It’s kind of a douchey move, and the part of her that’s scoffed at guys doing this for the past ten years dies a little, but the part of her that’s hungry for Keith’s attention is thriving. 

At least, it’s thriving until the neckline catches tragically on her chin, which has never happened since she taught herself to take shirts off like this. She’s stuck for a moment, a wriggling fool with her face framed by the black shirt pulled taut over her head like a bad nun costume. Serves her right for pulling this move. 

Keith is laughing, not unkindly. “Here—” she says, and Shiro’s breath catches as Keith reaches out to pluck at the shirt until it pulls free. Her fingers brush Shiro’s bangs when she draws back. 

Shiro laughs too, shaking off embarrassment and flustered nerves. Walking into the cage for the last time in just a black sports bra, she braces her hands on the bar to highlight her shoulders and catches Keith’s eye through the mirror as she flicks white-streaked bangs out of her face. 

She’d like to think Keith’s face is red from more than exercise. 

“I might need a spot for this one,” Shiro admits when she gets the bar on her shoulders. It’s not just an excuse for proximity; she’s been pushing herself today, with good reason, and this is the heaviest weight yet. 

Keith comes up close behind her, feet wide in a sturdy stance and hands poised to assist so close to Shiro’s. Shiro can feel her breath on her near-naked back, can see the rise and fall of her own chest in the mirror and the clench of her abs stabilizing the weight on her shoulders. It’s intimate, physically at least, and maybe the flutter passing from her heart to all her limbs is part of the reason she manages only two reps before her legs start giving out. 

“Keith,” she grits out on her way up from the third, stuck halfway to standing. 

“I've got you,” Keith murmurs. Her hands come up to the bar and take just enough of the weight so that Shiro can stand the rest of the way, and she stays with her as Shiro stumbles forward to rack the weight. 

“Thanks,” says Shiro, panting and truly exhausted. 

“No problem.” 

She meets Keith’s eye through the mirror, and then face to face when Shiro turns around, so close that she has to angle her head down. Her mind blanks like it did the first time this happened not half an hour ago, except that now they’re sweaty and pink and no longer strangers. Now she knows that Keith is as intriguing to talk to as she is to look at, has glimpsed her insecurities, has exposed her own hapless clumsiness. It’s at once less and more to deal with. 

Shiro doesn’t want to go back to fleeting glances over the card reader. 

“Hey,” she blurts before she can overthink it. “You got plans after this?” 

Keith shrugs, head tilting to the side in a way that’s endearingly cat-like. “Not really.” 

“I usually go get a smoothie,” Shiro presses on. “To replenish the nutrients.” 

“Yeah?” There’s a little smile playing at Keith’s lips—teasing, Shiro thinks. Hopes. “Nutrients are important.” 

“Do you, uh.” Shiro has faced illness and injury and heartbreak. She can do this. “Do you want to go to Vrepit Shakes? Together?” 

Keith smiles fully now, sweaty and gorgeous. “Yeah,” she says. “Yeah, I do.” 

* 

Three months later, when Shiro’s phone glitches again and her alarm fails to go off, she wakes instead to warm lips on her neck and a firm hand on her ass. “Gym time,” Keith murmurs into her skin. 

“Morning, baby.” She blinks her eyes slowly open to see Keith looking at her so softly, barely illuminated in the low shadows of dawn. Unfiltered in the hazy remnants of sleep, her next words come without thought, but with every deepest intention: “I love you.” 

Keith freezes, then presses her lips hard against Shiro’s. “I love you, too,” she breathes, and then they’re laughing, and Shiro tackles her back with a moan. 

For once, they skip the gym. 

**Author's Note:**

> what started as personal gym salt spiraled into a sheith au and then a fem sheith au!!! i can only hope i did this concept justice, seeing as i haven't been writing fic for very long. gym fem sheith has a special place in my heart <3 <3 <3 
> 
> please leave a comment/kudos if you enjoyed it, no matter how long it's been! 
> 
> big thanks to juna for encouraging this :) 
> 
> say hi on twitter! [@leftishark_](https://twitter.com/leftishark_)

**Works inspired by this one:**

  * [[Podfic] girl flex by leftishark](https://archiveofourown.org/works/20473250) by [taikodragon (hana_ginkawa)](https://archiveofourown.org/users/hana_ginkawa/pseuds/taikodragon)




End file.
